As Microsoft confirms it is laying off 18,000 workers, mainly in the mobile phone business it bought from Nokia, iPhone maker Foxconn has confirmed it has hired 100,000 new workers to manufacture the iPhone 6.

It comes as 4.7-inch iPhone production is expected to start next week, with the larger 5.5inch version set to start three weeks later.

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A leaked image, posted on Twitter by SonnyDickson in June, shows the difference in size between the current iPhone 5S (left) and the 'iPhone6' (left)

WHAT IS SAPPHIRE GLASS?

Synthetic sapphire is a hard, transparent material made of crystallising aluminium oxide, produced at high temperatures.

As
the material is heated, it forms disks that can be sliced
using diamond-coated saws.

These round disks are ground into shape, and
polished, to become glass.

The technology is traditionally used in watch displays because it is thin, super-strong and scratch resistant.

Apple already uses sapphire crystal in
the Touch ID fingerprint scanner on its latest iPhone 5S and to protects the phone's camera.

As a result, sapphire glass could potentially replace Gorilla Glass currently used in most high-end smartphones.

The Economic Daily said Foxconn had finally confirmed the rumours it would hire a huge number of staff.

'As in-cell touch panel becomes larger in size, the edge of the panel may become insensitive to touch.

'Meanwhile, under new manufacturing process for the iPhone 6 metal casing, color unevenness is an issue.'

According to 9th5mac, Kuo says that these problems become more complicated with the larger 5.5-inch iPhone 6.

'As these new concerns are coupled with earlier concerns about the production of sapphire displays for the larger device, the analyst believes that the 5.5-inch iPhone 6 may not launch by the end of 2014, or may launch after October in very limited quantities.'

Kuo also believes that Apple will cut the prices of the iPhone 5s and iPhone 5c alongside the launch of the 4.7-inch iPhone 6.

Prolific Apple-tipster, Sonny Dickson, has got his hands on leaked images of the front and back of a possible Apple LCD backlight panel that measures 5.5 inches (14cm). The photos suggest Apple is already producing components for its anticipated 5.5-inch phone

Previous leaks have claimed the handset will have a virtually indestructible screen made of sapphire.

A YouTube videomaker claims to have acquired one of the screens - and has subjected it to a barrage of abuse, from stabbing it with a knife and keys to bending and twisting it.

In the video, the screen emerges totally unscathed - raising hopes is could lead to a far more resilient handset from Apple.

Marques Brownlee, a popular YouTube host claims to have got the screen from well known Apple leaker Sonny Dickson, who recently made his own video showcasing the screen.

Sources 'familiar with the matter' said: 'The different timetables have been set as Apple does not want to repeat the mistake it made in 2013 when it launched the iPhone 5S (pictured front) and iPhone 5C (pictured back) simultaneously'

In the video he can be seen bending and twisting the screen.

'I slowly realized there is absolutely no way I can break this display under my own power,' he said.

'The worst blemish on the surface was actually my fingerprint marks and the dust from handling it so much.'

The glass is also extremely high-quality, Brownlee noted: 'There’s absolutely no color shift while looking through the sapphire glass.'

The iPhone 6 screen being repeatedly stabbed by a knife: The sapphire glass emerges unscathed from the video trial which also sees in being bent and scratched with keys

It is claimed the screen is made from sapphire crystal.

Apple already uses a small amount of sapphire glass for the 'Home' button and camera lens in the iPhone 5S, but the rest of the current iPhone front display is made of Gorilla Glass.

The new glass display is 'paper thin,' Brownlee said in his video.

Brownlee shows his screen measures 4.7 inches diagonally, keeping with rumors that Apple will release two different-sized iPhones this year: A 4.7-inch model and 5.5-inch one.

Reports Apple was experimenting with sapphire displays began last year, yet sources claimed at the time Apple found the technology ‘infeasible.’

In the video, Marques Brownlee stands on the thin screen and bends it. When released, it goes back it its normal shape, raising hopes the new handset will have an almost indestructible screen

The screen is also shown being repeatedly stabbed by a knife - and emerging with no scratches, although it has not been confirmed to be the 'official' screen that will feature in the new handset

This was because sapphire glass is more expensive to produce than normal screens.

However, Apple recently announced plans to open a mineral plant in Arizona with sapphire glass experts GT Advanced Technologies.

The facility is expected to employ around 700 people to manufacture sapphire crystal and sapphire glass, and this technology could make its way onto the screens of the next iPhone.

The screen is described as 'paper thin'. It is claimed to be made from thin man-made layers of sapphire, which enables the material to be flexible, giving it a change of withstanding knocks and falls that shatter other types of toughened glass

In the video, the screen survived having keys scratched across its surface - a common problem for iPhone owners who keep their handsets in their pocket

In a statement about the announcement, GT Advanced Technologies said: ‘Although the agreement does not guarantee volumes, it does require GT to maintain a minimum level of capacity.’

While an Apple spokesman added: 'We are proud to expand our domestic manufacturing initiative with a new facility in Arizona, creating more than 2,000 jobs in engineering, manufacturing and construction.

‘This new plant will make components for Apple products and it will run on 100 per cent renewable energy from day one, as a result of the work we are doing with SRP to create green energy sources to power the facility.’

Earlier this week iPhone maker Foxconn revealed Apple's new iPhone 6 could be the first to be made using its 'robot army'.

The firm has pledged to have a million robot workers by the end of the year - and CEO Terry Gou has revealed the robots, dubbed 'Foxbots', are in the final stages of testing.

It is believed Foxconn will install 10,000 robots as a test.

Workers are seen inside a Foxconn factory in the township of Longhua in the southern Guangdong province. The firm is believed to be installing thousands of robots to help build Apple's latest iPhone

Lines dedicated to Apple devices getting first priority, according to IT Home.

It says Gou told a shareholder meeting that Apple would be the first company to take advantage of the new robot workers meaning that its next product - the iPhone 6 - will be manufactured in this way.

Each $25,000 Foxbot can complete an average of 30,000 devices per year it has been claimed.

Foxconn, which currently employs more than 1.2 million workers at its various factories across China.

However, the firm's robot initiative has been delayed since it was first announced in 2011.

At the time, Gou said the company had about 10,000 units already in operation, a number that was supposed to rise to 300,000 in 2012, then one million by 2014.

However, the firm is also ramping up human workers for the iPhone 6, with 100,00 being hired according to some reports.

Dozens of pictures have leaked online claiming to show Apple's iPhone 6.

They all show a thin, curved device with distinctive white 'bars' across the back.

However, a Japanese news agency has claimed that in fact, the finished product will look very different - and that it could even have a curved screen.